Staging
v0.8.1
v0.8.1
https://github.com/torvalds/linux
Tip revision: f0e615c3cb72b42191b558c130409335812621d8 authored by Linus Torvalds on 19 April 2011, 04:26:00 UTC
Linux 2.6.39-rc4
Linux 2.6.39-rc4
Tip revision: f0e615c
ad7606_core.c
/*
* AD7606 SPI ADC driver
*
* Copyright 2011 Analog Devices Inc.
*
* Licensed under the GPL-2.
*/
#include <linux/interrupt.h>
#include <linux/workqueue.h>
#include <linux/device.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/sysfs.h>
#include <linux/list.h>
#include <linux/regulator/consumer.h>
#include <linux/err.h>
#include <linux/gpio.h>
#include <linux/delay.h>
#include <linux/sched.h>
#include "../iio.h"
#include "../sysfs.h"
#include "../ring_generic.h"
#include "adc.h"
#include "ad7606.h"
int ad7606_reset(struct ad7606_state *st)
{
if (st->have_reset) {
gpio_set_value(st->pdata->gpio_reset, 1);
ndelay(100); /* t_reset >= 100ns */
gpio_set_value(st->pdata->gpio_reset, 0);
return 0;
}
return -ENODEV;
}
static int ad7606_scan_direct(struct ad7606_state *st, unsigned ch)
{
int ret;
st->done = false;
gpio_set_value(st->pdata->gpio_convst, 1);
ret = wait_event_interruptible(st->wq_data_avail, st->done);
if (ret)
goto error_ret;
if (st->have_frstdata) {
ret = st->bops->read_block(st->dev, 1, st->data);
if (ret)
goto error_ret;
if (!gpio_get_value(st->pdata->gpio_frstdata)) {
/* This should never happen */
ad7606_reset(st);
ret = -EIO;
goto error_ret;
}
ret = st->bops->read_block(st->dev,
st->chip_info->num_channels - 1, &st->data[1]);
if (ret)
goto error_ret;
} else {
ret = st->bops->read_block(st->dev,
st->chip_info->num_channels, st->data);
if (ret)
goto error_ret;
}
ret = st->data[ch];
error_ret:
gpio_set_value(st->pdata->gpio_convst, 0);
return ret;
}
static ssize_t ad7606_scan(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct iio_dev *dev_info = dev_get_drvdata(dev);
struct ad7606_state *st = dev_info->dev_data;
struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
int ret;
mutex_lock(&dev_info->mlock);
if (iio_ring_enabled(dev_info))
ret = ad7606_scan_from_ring(st, this_attr->address);
else
ret = ad7606_scan_direct(st, this_attr->address);
mutex_unlock(&dev_info->mlock);
if (ret < 0)
return ret;
return sprintf(buf, "%d\n", (short) ret);
}
static IIO_DEV_ATTR_IN_RAW(0, ad7606_scan, 0);
static IIO_DEV_ATTR_IN_RAW(1, ad7606_scan, 1);
static IIO_DEV_ATTR_IN_RAW(2, ad7606_scan, 2);
static IIO_DEV_ATTR_IN_RAW(3, ad7606_scan, 3);
static IIO_DEV_ATTR_IN_RAW(4, ad7606_scan, 4);
static IIO_DEV_ATTR_IN_RAW(5, ad7606_scan, 5);
static IIO_DEV_ATTR_IN_RAW(6, ad7606_scan, 6);
static IIO_DEV_ATTR_IN_RAW(7, ad7606_scan, 7);
static ssize_t ad7606_show_scale(struct device *dev,
struct device_attribute *attr,
char *buf)
{
/* Driver currently only support internal vref */
struct iio_dev *dev_info = dev_get_drvdata(dev);
struct ad7606_state *st = iio_dev_get_devdata(dev_info);
unsigned int scale_uv = (st->range * 1000 * 2) >> st->chip_info->bits;
return sprintf(buf, "%d.%03d\n", scale_uv / 1000, scale_uv % 1000);
}
static IIO_DEVICE_ATTR(in_scale, S_IRUGO, ad7606_show_scale, NULL, 0);
static ssize_t ad7606_show_name(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct iio_dev *dev_info = dev_get_drvdata(dev);
struct ad7606_state *st = iio_dev_get_devdata(dev_info);
return sprintf(buf, "%s\n", st->chip_info->name);
}
static IIO_DEVICE_ATTR(name, S_IRUGO, ad7606_show_name, NULL, 0);
static ssize_t ad7606_show_range(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct iio_dev *dev_info = dev_get_drvdata(dev);
struct ad7606_state *st = iio_dev_get_devdata(dev_info);
return sprintf(buf, "%u\n", st->range);
}
static ssize_t ad7606_store_range(struct device *dev,
struct device_attribute *attr, const char *buf, size_t count)
{
struct iio_dev *dev_info = dev_get_drvdata(dev);
struct ad7606_state *st = iio_dev_get_devdata(dev_info);
unsigned long lval;
if (strict_strtoul(buf, 10, &lval))
return -EINVAL;
if (!(lval == 5000 || lval == 10000)) {
dev_err(dev, "range is not supported\n");
return -EINVAL;
}
mutex_lock(&dev_info->mlock);
gpio_set_value(st->pdata->gpio_range, lval == 10000);
st->range = lval;
mutex_unlock(&dev_info->mlock);
return count;
}
static IIO_DEVICE_ATTR(range, S_IRUGO | S_IWUSR, \
ad7606_show_range, ad7606_store_range, 0);
static IIO_CONST_ATTR(range_available, "5000 10000");
static ssize_t ad7606_show_oversampling_ratio(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct iio_dev *dev_info = dev_get_drvdata(dev);
struct ad7606_state *st = iio_dev_get_devdata(dev_info);
return sprintf(buf, "%u\n", st->oversampling);
}
static int ad7606_oversampling_get_index(unsigned val)
{
unsigned char supported[] = {0, 2, 4, 8, 16, 32, 64};
int i;
for (i = 0; i < ARRAY_SIZE(supported); i++)
if (val == supported[i])
return i;
return -EINVAL;
}
static ssize_t ad7606_store_oversampling_ratio(struct device *dev,
struct device_attribute *attr, const char *buf, size_t count)
{
struct iio_dev *dev_info = dev_get_drvdata(dev);
struct ad7606_state *st = iio_dev_get_devdata(dev_info);
unsigned long lval;
int ret;
if (strict_strtoul(buf, 10, &lval))
return -EINVAL;
ret = ad7606_oversampling_get_index(lval);
if (ret < 0) {
dev_err(dev, "oversampling %lu is not supported\n", lval);
return ret;
}
mutex_lock(&dev_info->mlock);
gpio_set_value(st->pdata->gpio_os0, (ret >> 0) & 1);
gpio_set_value(st->pdata->gpio_os1, (ret >> 1) & 1);
gpio_set_value(st->pdata->gpio_os1, (ret >> 2) & 1);
st->oversampling = lval;
mutex_unlock(&dev_info->mlock);
return count;
}
static IIO_DEVICE_ATTR(oversampling_ratio, S_IRUGO | S_IWUSR,
ad7606_show_oversampling_ratio,
ad7606_store_oversampling_ratio, 0);
static IIO_CONST_ATTR(oversampling_ratio_available, "0 2 4 8 16 32 64");
static struct attribute *ad7606_attributes[] = {
&iio_dev_attr_in0_raw.dev_attr.attr,
&iio_dev_attr_in1_raw.dev_attr.attr,
&iio_dev_attr_in2_raw.dev_attr.attr,
&iio_dev_attr_in3_raw.dev_attr.attr,
&iio_dev_attr_in4_raw.dev_attr.attr,
&iio_dev_attr_in5_raw.dev_attr.attr,
&iio_dev_attr_in6_raw.dev_attr.attr,
&iio_dev_attr_in7_raw.dev_attr.attr,
&iio_dev_attr_in_scale.dev_attr.attr,
&iio_dev_attr_name.dev_attr.attr,
&iio_dev_attr_range.dev_attr.attr,
&iio_const_attr_range_available.dev_attr.attr,
&iio_dev_attr_oversampling_ratio.dev_attr.attr,
&iio_const_attr_oversampling_ratio_available.dev_attr.attr,
NULL,
};
static mode_t ad7606_attr_is_visible(struct kobject *kobj,
struct attribute *attr, int n)
{
struct device *dev = container_of(kobj, struct device, kobj);
struct iio_dev *dev_info = dev_get_drvdata(dev);
struct ad7606_state *st = iio_dev_get_devdata(dev_info);
mode_t mode = attr->mode;
if (st->chip_info->num_channels <= 6 &&
(attr == &iio_dev_attr_in7_raw.dev_attr.attr ||
attr == &iio_dev_attr_in6_raw.dev_attr.attr))
mode = 0;
else if (st->chip_info->num_channels <= 4 &&
(attr == &iio_dev_attr_in5_raw.dev_attr.attr ||
attr == &iio_dev_attr_in4_raw.dev_attr.attr))
mode = 0;
else if (!st->have_os &&
(attr == &iio_dev_attr_oversampling_ratio.dev_attr.attr ||
attr ==
&iio_const_attr_oversampling_ratio_available.dev_attr.attr))
mode = 0;
else if (!st->have_range &&
(attr == &iio_dev_attr_range.dev_attr.attr ||
attr == &iio_const_attr_range_available.dev_attr.attr))
mode = 0;
return mode;
}
static const struct attribute_group ad7606_attribute_group = {
.attrs = ad7606_attributes,
.is_visible = ad7606_attr_is_visible,
};
static const struct ad7606_chip_info ad7606_chip_info_tbl[] = {
/*
* More devices added in future
*/
[ID_AD7606_8] = {
.name = "ad7606",
.bits = 16,
.sign = IIO_SCAN_EL_TYPE_SIGNED,
.int_vref_mv = 2500,
.num_channels = 8,
},
[ID_AD7606_6] = {
.name = "ad7606-6",
.bits = 16,
.sign = IIO_SCAN_EL_TYPE_SIGNED,
.int_vref_mv = 2500,
.num_channels = 6,
},
[ID_AD7606_4] = {
.name = "ad7606-4",
.bits = 16,
.sign = IIO_SCAN_EL_TYPE_SIGNED,
.int_vref_mv = 2500,
.num_channels = 4,
},
};
static int ad7606_request_gpios(struct ad7606_state *st)
{
struct gpio gpio_array[3] = {
[0] = {
.gpio = st->pdata->gpio_os0,
.flags = GPIOF_DIR_OUT | ((st->oversampling & 1) ?
GPIOF_INIT_HIGH : GPIOF_INIT_LOW),
.label = "AD7606_OS0",
},
[1] = {
.gpio = st->pdata->gpio_os1,
.flags = GPIOF_DIR_OUT | ((st->oversampling & 2) ?
GPIOF_INIT_HIGH : GPIOF_INIT_LOW),
.label = "AD7606_OS1",
},
[2] = {
.gpio = st->pdata->gpio_os2,
.flags = GPIOF_DIR_OUT | ((st->oversampling & 4) ?
GPIOF_INIT_HIGH : GPIOF_INIT_LOW),
.label = "AD7606_OS2",
},
};
int ret;
ret = gpio_request_one(st->pdata->gpio_convst, GPIOF_OUT_INIT_LOW,
"AD7606_CONVST");
if (ret) {
dev_err(st->dev, "failed to request GPIO CONVST\n");
return ret;
}
ret = gpio_request_array(gpio_array, ARRAY_SIZE(gpio_array));
if (!ret) {
st->have_os = true;
}
ret = gpio_request_one(st->pdata->gpio_reset, GPIOF_OUT_INIT_LOW,
"AD7606_RESET");
if (!ret)
st->have_reset = true;
ret = gpio_request_one(st->pdata->gpio_range, GPIOF_DIR_OUT |
((st->range == 10000) ? GPIOF_INIT_HIGH :
GPIOF_INIT_LOW), "AD7606_RANGE");
if (!ret)
st->have_range = true;
ret = gpio_request_one(st->pdata->gpio_stby, GPIOF_OUT_INIT_HIGH,
"AD7606_STBY");
if (!ret)
st->have_stby = true;
if (gpio_is_valid(st->pdata->gpio_frstdata)) {
ret = gpio_request_one(st->pdata->gpio_frstdata, GPIOF_IN,
"AD7606_FRSTDATA");
if (!ret)
st->have_frstdata = true;
}
return 0;
}
static void ad7606_free_gpios(struct ad7606_state *st)
{
if (st->have_range)
gpio_free(st->pdata->gpio_range);
if (st->have_stby)
gpio_free(st->pdata->gpio_stby);
if (st->have_os) {
gpio_free(st->pdata->gpio_os0);
gpio_free(st->pdata->gpio_os1);
gpio_free(st->pdata->gpio_os2);
}
if (st->have_reset)
gpio_free(st->pdata->gpio_reset);
if (st->have_frstdata)
gpio_free(st->pdata->gpio_frstdata);
gpio_free(st->pdata->gpio_convst);
}
/**
* Interrupt handler
*/
static irqreturn_t ad7606_interrupt(int irq, void *dev_id)
{
struct ad7606_state *st = dev_id;
if (iio_ring_enabled(st->indio_dev)) {
if (!work_pending(&st->poll_work))
schedule_work(&st->poll_work);
} else {
st->done = true;
wake_up_interruptible(&st->wq_data_avail);
}
return IRQ_HANDLED;
};
struct ad7606_state *ad7606_probe(struct device *dev, int irq,
void __iomem *base_address,
unsigned id,
const struct ad7606_bus_ops *bops)
{
struct ad7606_platform_data *pdata = dev->platform_data;
struct ad7606_state *st;
int ret;
st = kzalloc(sizeof(*st), GFP_KERNEL);
if (st == NULL) {
ret = -ENOMEM;
goto error_ret;
}
st->dev = dev;
st->id = id;
st->irq = irq;
st->bops = bops;
st->base_address = base_address;
st->range = pdata->default_range == 10000 ? 10000 : 5000;
ret = ad7606_oversampling_get_index(pdata->default_os);
if (ret < 0) {
dev_warn(dev, "oversampling %d is not supported\n",
pdata->default_os);
st->oversampling = 0;
} else {
st->oversampling = pdata->default_os;
}
st->reg = regulator_get(dev, "vcc");
if (!IS_ERR(st->reg)) {
ret = regulator_enable(st->reg);
if (ret)
goto error_put_reg;
}
st->pdata = pdata;
st->chip_info = &ad7606_chip_info_tbl[id];
atomic_set(&st->protect_ring, 0);
st->indio_dev = iio_allocate_device();
if (st->indio_dev == NULL) {
ret = -ENOMEM;
goto error_disable_reg;
}
st->indio_dev->dev.parent = dev;
st->indio_dev->attrs = &ad7606_attribute_group;
st->indio_dev->dev_data = (void *)(st);
st->indio_dev->driver_module = THIS_MODULE;
st->indio_dev->modes = INDIO_DIRECT_MODE;
init_waitqueue_head(&st->wq_data_avail);
ret = ad7606_request_gpios(st);
if (ret)
goto error_free_device;
ret = ad7606_reset(st);
if (ret)
dev_warn(st->dev, "failed to RESET: no RESET GPIO specified\n");
ret = request_irq(st->irq, ad7606_interrupt,
IRQF_TRIGGER_FALLING, st->chip_info->name, st);
if (ret)
goto error_free_gpios;
ret = ad7606_register_ring_funcs_and_init(st->indio_dev);
if (ret)
goto error_free_irq;
ret = iio_device_register(st->indio_dev);
if (ret)
goto error_free_irq;
ret = iio_ring_buffer_register(st->indio_dev->ring, 0);
if (ret)
goto error_cleanup_ring;
return st;
error_cleanup_ring:
ad7606_ring_cleanup(st->indio_dev);
iio_device_unregister(st->indio_dev);
error_free_irq:
free_irq(st->irq, st);
error_free_gpios:
ad7606_free_gpios(st);
error_free_device:
iio_free_device(st->indio_dev);
error_disable_reg:
if (!IS_ERR(st->reg))
regulator_disable(st->reg);
error_put_reg:
if (!IS_ERR(st->reg))
regulator_put(st->reg);
kfree(st);
error_ret:
return ERR_PTR(ret);
}
int ad7606_remove(struct ad7606_state *st)
{
struct iio_dev *indio_dev = st->indio_dev;
iio_ring_buffer_unregister(indio_dev->ring);
ad7606_ring_cleanup(indio_dev);
iio_device_unregister(indio_dev);
free_irq(st->irq, st);
if (!IS_ERR(st->reg)) {
regulator_disable(st->reg);
regulator_put(st->reg);
}
ad7606_free_gpios(st);
kfree(st);
return 0;
}
void ad7606_suspend(struct ad7606_state *st)
{
if (st->have_stby) {
if (st->have_range)
gpio_set_value(st->pdata->gpio_range, 1);
gpio_set_value(st->pdata->gpio_stby, 0);
}
}
void ad7606_resume(struct ad7606_state *st)
{
if (st->have_stby) {
if (st->have_range)
gpio_set_value(st->pdata->gpio_range,
st->range == 10000);
gpio_set_value(st->pdata->gpio_stby, 1);
ad7606_reset(st);
}
}
MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
MODULE_DESCRIPTION("Analog Devices AD7606 ADC");
MODULE_LICENSE("GPL v2");